Not all epidemologists are in agreement.
Sweden's has basically said the costs of shutting down until a vaccine is found (or until the numbers are low enough you can test-and-track and impose quaruntine or testing on all visitors to the country) are worse than just letting it run its course.
Bare in mind that all government decisions are heavily biased by the optics of that decision, as seen by the average voter when passed through a media filter. If it genuinely cost more QALYs to implement shutdown+exit strategy than just "attempt mitigation with focus on elderly and delay things until you've got enough equipment", it would still be very hard to argue that viewpoint in front of the media.
Arguing "The economy is more important than grandma!" is very difficult, requiring a dive into life expectancy, quality of life metrics, isolation side effects, economic depression side effects, QALYs and what exactly an "economy" even is (and, importantly, what it isn't, like all the non-captured-by-gdp utility gained by just hanging out with friends in the park). Can you imagine a politician trying to argue that grandma is a necessary sacrifice in front of the cameras?
Admittedly, making such an argument isn't impossible: https://www.dailymail.co.uk/debate/article-8281007/amp/Forme...